The unit started successfully on its first attempt and is now running steadily. The liquid sulphur product meets first-grade quality requirements, and all main operating targets have been reached. The project helps the oilfield improve production while supporting cleaner and lower-carbon development.
Ruichang International has supported the successful start-up of the sulphur recovery expansion project at Manshen Central Processing Station in the Tarim Oilfield. The process package was jointly developed by Ruichang International and the Design Branch of CNPC (Xinjiang) Petroleum Engineering Co., Ltd.
A Solution for Difficult Feed Gas Conditions
Manshen Central Processing Station is located in the central area of the Taklamakan Desert. It mainly treats associated gas from oil production.
The feed gas has a low hydrogen sulphide content, a high level of heavy hydrocarbons and large changes in flow rate. These conditions are difficult for a sulphur recovery unit. The old unit could no longer meet current environmental standards or production needs, so an expansion and upgrade were necessary.
To deal with these challenges, Ruichang’s technical team worked closely with the main design institute. The team studied possible risks at an early stage and prepared a solution for the local operating conditions. It also improved the technical route on the basis of a mature process, helping the new unit start safely and run steadily.
Combined Technologies Improve Sulphur Recovery
The project uses a mature two-stage Claus process, followed by hydrogenation, reduction and amine absorption and regeneration. Ruichang also added several key technologies, including feed preheating, oxygen-enriched combustion, zone combustion and multi-stage hydrogen production.
This combined solution helps solve common problems such as unstable combustion and catalyst coking when treating feed gas with low sulphur and high heavy-hydrocarbon content.
The unit has an operating range of 30% to 110%, giving it the flexibility to handle changes in feed-gas flow. Its total sulphur recovery rate remains above 99.8%. Emissions such as sulphur dioxide and nitrogen oxides are below the limits of China’s GB 39728-2020 standard.
The project also brings clear environmental and resource benefits. It can recover 6,600 tonnes of sulphur each year and reduce sulphur dioxide emissions by 13,200 tonnes per year. This turns sulphur in the feed gas into a useful product while supporting cleaner production.
Two Key Equipment Improvements
Ruichang made two important improvements to the main equipment.
First, the reduction furnace uses a step-by-step mixing and cooling structure for hot and cold fluids. This design helps solve the vibration problems often found in traditional furnace designs.
Second, the tail-gas incinerator also works as a start-up boiler. This integrated design reduces the number of equipment items and lowers investment. It also provides a practical solution when steam is not available during the early start-up stage at a desert site.
These improvements offer a useful reference for future sulphur recovery projects in remote oilfields.
Modular Construction for a Desert Site
Construction in the Taklamakan Desert is difficult. The schedule was tight, site conditions were poor and outdoor work involved higher safety risks.
For this reason, the project used a fully modular and skid-mounted design. About 90% of the unit was modularised. Equipment, piping, instruments and control systems were prefabricated, assembled, tested and checked for gas tightness at Ruichang’s production base.
At the project site, the main work was module matching and bolt connection. This greatly reduced the amount of field construction. The modular method shortened the project schedule by more than 40 days and lowered safety and quality risks at the remote site.
The unit can also be moved and reused in the future. This gives the owner greater safety, flexibility and cost control.
Full-Service Support from Design to Start-Up
Throughout the project, Ruichang worked closely with the owner and the main design institute. The company provided support at every main stage:
- During the early stage, Ruichang offered technical support for the project design and matched the process to the feed-gas conditions.
- During manufacturing, the team managed modular design, factory production and full testing before delivery.
- During site work, technical specialists guided module assembly, system checks, gas-tightness testing and trial operation.
- During start-up, an experienced team stayed on site to guide feed introduction and help the unit start successfully on its first attempt.
The successful operation of this project shows Ruichang’s ability to combine process technology, modular equipment and full-service project support.
Ruichang International will continue to develop energy-saving, integrated and modular technologies for the oil and gas industry. Through its own technologies, standardised delivery and full-service support, the company aims to help oil and gas producers improve efficiency, reduce emissions and move towards lower-carbon development.
About Ruichang International
Ruichang International Holdings Limited (1334.HK) provides air-pollution control and energy-saving solutions for industrial thermal energy projects. Its business covers combustion, waste-heat recovery, catalysis, sulphur recovery and incineration, plume control and low-temperature waste-heat use. The company provides engineering and modular equipment solutions for customers in the petroleum, petrochemical, natural gas and related industries.
